Asmus P A, Freed C R
J Chromatogr. 1979 Feb 1;169:303-11. doi: 10.1016/0021-9673(75)85054-0.
We have investigated the value of various common acids as ion-pairing reagents for high-efficiency separations of catecholamines and their metabolites in reversed-phase high-performance liquid chromatography. The retention of norepinephrine, alpha-methylnorepinephrine, dopamine, alpha-methyldopamine, L-dopa, alpha-methyldopa, dihydroxybenzylamine, epinephrine, carbidopa and DOPAC was measured in mobile phases composed of nitric, sulfuric, acetic and trichloroacetic acids at pH 2-5 and anion concentrations ranging from 5-500 mM. The solute capacity ratios were dependent on the hydrophobicity and concentration of the ion-pairing reagent and the pH of the mobile phase. Good retention, peak symmetry and high efficiency (3000 theoretical plates for 300 mm) was found for mobile phases composed of the strong inorganic acids and trichloroacetic acid. Chromatography was compared to that seen using the detergent sodium octylsulfate. Trichloroacetic acid gave retention and efficiency similar to sodium octylsulfate. These experiments show that simple acids can replace alkylsulfates as ion-pairing reagents for the separation of the catecholamines and their metabolites.
我们研究了各种常见酸作为离子对试剂在反相高效液相色谱法中对儿茶酚胺及其代谢物进行高效分离的价值。在由硝酸、硫酸、乙酸和三氯乙酸组成的pH值为2 - 5且阴离子浓度范围为5 - 500 mM的流动相中，测定了去甲肾上腺素、α-甲基去甲肾上腺素、多巴胺、α-甲基多巴胺、L-多巴、α-甲基多巴、二羟基苄胺、肾上腺素、卡比多巴和3,4-二羟基苯乙酸的保留情况。溶质容量比取决于离子对试剂的疏水性和浓度以及流动相的pH值。对于由强无机酸和三氯乙酸组成的流动相，发现具有良好的保留、峰对称性和高效率（300 mm柱长有3000理论塔板数）。将该色谱法与使用去污剂辛基硫酸钠的情况进行了比较。三氯乙酸的保留和效率与辛基硫酸钠相似。这些实验表明，简单的酸可以替代烷基硫酸盐作为离子对试剂用于儿茶酚胺及其代谢物的分离。
